A lot of questions arise from The King's Speech, the recent film in which - spoiler alert - a king can't speak very well, but then manages to, thanks to an Australian. Among these questions: for how many decades must the rest of us men be judged by the impossible standards of sexiness set by Colin Firth? Did Edward VIII really want to marry the seemingly irritating Wallis Simpson, or did he just want to get out of being king, since it's clearly no fun? And in the script, d . . . d . . . did the screenwriters have to write out every stammer l . . . l . . . like this, or was it covered by the stage directions?

But there's one question that arises from the tense final scene, in which our hero rises to the challenge of delivering a long and rousing speech to his subjects. Could they not have recorded him doing it and played it half an hour later, removing the possibility that the King's erratic voice would fail live on air and thus deal a blow to Britain's spirit on the brink of war?

Earlier in the film, we see that the technology existed to record His Majesty's efforts, because his Australian guru does just that. Even if editing in 1939 was less a matter of going into a Soho suite with a couple of Macs and more a case of someone taking a hacksaw to a piece of vinyl, surely it would have been possible to spare the King the ordeal? It wouldn't have been quite so dramatic a climax to the film - "right, Your Majesty, a couple of little slip-ups there, but we'll snip those out" - but it would have been a lot less stressful for all concerned, at a time when Hitler was causing quite enough stress for most people.

The answer to this riddle, it seems, has less to do with technological shortcomings and more to do with a faith in the idea of live broadcasting. The BBC in its infancy broadcast everything live, not purely because of logistics, but because that was the only way it could enjoy the trust of its listeners. If its material could be recorded, edited and fiddled with, how were we meant to rely on BBC radio for all the things for which we have usually relied on it: news, national morale and very slow-moving farming dramas?

A fascinating book by Denis Norden called Coming to You Live! recounts some of the problems the BBC faced in the 1940s and 1950s as a result of this dedication to live broadcasting. There's one anecdote about a drama that involved what was then the longest tracking shot in history, the camera making its way down an endless line of violinists; but they could only afford four violinists, so the actors had to keep running down the line and appearing again and again. There's another one about a play that was all ready to go when someone realised the BBC hadn't paid for the rights and wouldn't be allowed to broadcast it. When they turned up that morning, the actors were told they'd have to learn a new play from scratch.

All this makes you wonder whether live broadcasting is worth the misery - and yet idiots will keep trying it. And by idiots, I mean myself. On 28 February, I'm doing a special edition of my Radio 4 show absolutely live. This might sound like a plug, but it's not: I'm not even going to tell you what time it's on. The amount that can go wrong is terrifying.

The prospect of saying something obscene by accident - like James Naughtie giving an extra "C" to Jeremy Hunt - looms large, as does the even worse idea of being swept away by that I-might-jump-off-the-top-of-this-building impulse and sabotaging the whole show by shouting nothing but the word "duck" over and over again, just because I can. Then there's the worry that I might completely blank and leave minute after minute of silence on the air. Producers would have to hope listeners would mistake it for a particularly stodgy episode of The Archers.

The King and I

But these dangers are precisely the reason everyone still loves listening to live shows. They're pretty similar to the reasons poor old King George had to brave the microphone all those years ago. We like listening to the tremor in someone's voice, knowing that the anticipation in their guts at the sound of the opening credits is exactly the same as ours.

Above all, we like feeling that we're experiencing exactly the same thing as the person on the other end of the wire. Which is all very well for you, but awful for the King, and - in a rather less high-stakes way - scary for me, too. I don't even have the benefit of a dauntless Aussie to see me through by making me sing. We'll just have to hope that I can channel some of whatever magical BBC energy helped the King. Anyway, I have to make a phone call. I'm trying to get hold of 79 violinists.